Pendulum scale



Jan. 1s, 1927. 1,614,726A` W. N. GILBERT PENDULUM scALE Jan. 18,1927. V1,614,726

W. N. GILBERT PNDuLuu SCALE Filed oct. 12. 1925 3 Sheets-Sheet 2 Patented Jan. 18, 1927.

UNITED STATES PATENT OFFICE.

WILLIAM N. GILBERT, OF HUDSON-HEIGHTS, NEW JEBSEYQASSIGNOR TO DAYTON SCALE COMPANY, OF DAYTON, O HIO, A CORPORATION 0F NEW JERSEY.

PENDULUM SCALE.

Application filed October` 12, 1925. Serial No. 61,928.

This invention pertains to automatic weighing scales of the pendulum type and has for its principal object the provision of a scale of that type which will not be thrown out of balance nor weigh inaccurately when the scale is out of level.

As is well known this has long been a1 difficult problem especially in scales of portable type which are frequently moved from place to place. The problem is solved in my present invention by the use of two similar pendulums so interconnected with each other and with the balance of the scalemechanism as to ena'ble the scale to automatically maintain its adjustments and accuracy within all ordinary out of level conditions.

Another ob'ect `of my invention is to provide a scale o such design as will be durable in service and maintain its adjustments over long periods of time. l Another object is to provide a sim le and compact arrangement of load counter alancin means whlch will lend itself readily to unit construction; thatis, the load offsetting mechanism may be built as a complete compact unit in itself and later installed in a suitable casing or housing with only slight modification to fit it to a particular type or capacity of scale.

urther and other objects and advantages will be hereinafter set forth in the accompanyin `specifications and claims and shown in the rawings, which by way of illustration show what is now considered to bethe preferred embodiment of the invention.

In the drawings,

Fig. lis a front view of my design with outer casingremoved. I

' Fig. 2 is a1 side view of Fig. 1 taken from the right. v

Fig. 3 is a detail of pendulum cam.'

Fig. 4 is a sectional view on line 4-4 of Fig. 1.

Fig. Fig. 1.

Fig. 6 is an enlarged view of the pendulums and connections. 5

. Fig. 7 is an enlarged view of a portion of main lever and rack rod check device.

5 is al sectional view on line 5-5 of The main lever 1() has a fulcrum pivot 12 resting in fulcrum bearing 14 supported on frame 16. Te the left of the lfulcrum bearing is a load pivot" 18 connected by steelyard rod 20 to the lever system contained within the base 22. The base levers are not shown 'fastened thereto.

as any system of levers suitable for use with automatic "load offsetting devices may be used. The load receiving platform 24 is carried by the base levers.

Pivotally connected at 26 to leverlO is the dash pot rod 28 provided at itv Llower end with a plunger working within t e cylinder of dash pot 30 to dampen the vibration of thet scale parts and bring them promptly to res Lever 10 4is formed of two similar side plates spaced apart and rigidlyv fastened together by `studs 32.

Near the left end of lever 10 is al pivot 34 from which extends upwardly a tape or ribbon 36 whichat its upper end passes partly around the circumference of cam 38 and `is Cam 38 is the well known devlce commonly used in pendulum scales to cou'nterbalance for the angularity of the pendulum swing thereby permitting the charts or dials to be evenly graduated.

Cam 38 is fast to pivot 40 which rests in fulcrum bearing 42' and carries left hand pendulum 44. On the right side ofthe machinea similar pendulum' 46 has a pivot 48 supported in fulcrum bearing 50. 'Extending laterally towards the center of the machine from pivots 40 and 48 are the arms 52 and 54 respectively. Each arm is adjustably secured by a slot and screw device to its pendulum, but after adjustment each arm isin effect integral with itsy respective pendulum. 'Arm 52 terminates in an arcuate portion -56 and 'arm 54 has an exactly similar arcuate portion 58 (Fig. 6). The two arcuate portlons 56 and 58vv are in close proximity to each other andare yoperably connected by metal tapes or sribbons, the

,upper end ofarc56 being connected by tape 60y to the lower end of arc. 58, and the upper end of arcl 58 being connected to the lower end of arc 56 by 4tape 62. It will be readily understood. that this construction provides a positive, frictionless connection between pendulums so that if either pendulum swings on its pivot the other will swing an exactly.

similar amount in the opposite direction. If one pendulum swings towards the centerv of the machine the other will also swing towards the center an exactly similar distance and 'if `one swings outwardly the other will also swing outwardly the same amount,

Hanging' downwardly from the arcuate surfaces 56and 58 is the loop of tape lor one of the upper free ends of the loop being secured to the upper end of arc 56 and the other to the upper end of arc 58. Resting in the loop at the lower end of 64 is the roller 66 (Figs. 4 and 6) fast on shaft 68,

the ends of which are mounted in anti-l friction bearings 70 in vertical yoke 72 bearing on its upper end the vertical rack rod 74. On the upper end of rod 74 is secured the rack 76 in mesh with pinion 78 which in the usual manner turns indicator 80 to indicate on chart or dial 82 the weight of the load on the platform. The lower end of yoke 72 is provided with the usual offset weight 84 to keep rack 76 gently enmeshed with pinion 78.

To guide the lower end of yoke 72 in a vertical path a check link 86 is provided with one end fast to shaft 68 and the other fast to shaft 88 mounted in antifriction bearings in the bracket 90 rigid with lever 10 andv projecting upwardly therefrom. The position of bracket 90 and its length are so proportioned with relation to length of link 86 and location of pivot 12 that shaft 68 travels in a vertical line as indicated in Fig. 7.

In operation, when a load is placed on platform 24 steelyard rod 20 is drawn down, lever 10 is, swung counter-clockwise about its fulcrum pivot 12 and tape 36 is drawn down. The drawing down of tape 36, 4acting through the instrumentality of cam 36 swings pendulums 44 and 46 equal amounts towards the centerof the machine until they have acquired suliicient leverage measured horizontally from their respective pivots 40 and 48 to counterbalance the load. and at those points they come to rest. This swinging of the pendulums has raised their arcuate members 52 and 54 and. with them, yoke 72 and rack 76 resulting in pinion 78 being rotated and causing indicator 80 to `point out on chart 82 the amount of the load. When the load is removed the pendulums b and other moving parts will return to normal position and the indicator will 4again indicate zero,

If the machine is shifted to an out of level position it will be evident that the effective leverage of'one pendulum will be increased and the leverage of the other decreased, the leverage being measured horizontally from their respective pivots, but

since the two pendulums are exactly similar, move in opposite directions, and are located symmetrically with reference to the center line of the machine, one pendulum will gain 4the same amount of leverage as the other loses. Therefore, since the pendulums are interconnected by frictionless means, they Will assume the same positions in counterbalancing any given load whether the scale i vis level or out of level, provided only that the machine is not so far out of level as to permit .working parts to become displaced indicator operating from their true cause friction.

Any disturbing effect on the weighing operations due to the indicating devices under out of level condition is'obviated by the fact that the-rack rod and the parts which actuate it are all on the center line of the machine.

In accordance with the provisions of the patent statutes, I have herein described the principle of operation of my invention, to- ;rether with the apparatus which I now consider to represent the best embodiments thereof, but I desire to have -it understood that the apparatus disclosed is only illustrative and that the invention can be carpositions sufficiently to ried out by other means. Also, while it is designed to use the various features and elements in the combinations and relations described, some of these may be altered and others omitted and some of the features of each modification may be embodied in the others without interfering with the more general results outlined, andthe invention extends to such use. I

What I claim is- 1. In a machine of the class described, weight indicating devices in combination with loa-d counterbalancing meanscomprising a pair of oppositely disposed pendulums, and frictionless means for directly interconnecting said pendulums and constraining said pendulums to operate in harmony.

2." The invention set forth in claim 1 in which said frictionless means comprises arcnate portions of the pendulum structure and weight indicating devices in combination with load counterbalancing means comprising a pair of oppositely disposed pendulums, said pendulums being provided with integral arcuate members` said arcuate members leing circumferentially adjacent land operably interconnected by frictionless means which constrains said pendulums to operate in harmony.

4. In a machine of the class described, weight indicating devices in combination with load counterbalancing means comprising a pair of oppositely disposed pendulums,

said pendulums being provided' with integral arcuate members, said arcuate members being substantially tangent to each other and being interconnected by crossed tapes, one of which extends from the upper portion of each arcuate surface to the lower portion of the other arcuate surface. y

'5. In a load .counterbalancing and indieating mechanism for an automatic scale, in combination, a.I pair of oppositely disposed pendulums, frictionless means for interconnecting said pendulums and constraining said pendulums to operate in harmony, an device, and frictionless means for interconnecting said pendulums interconnecting said members, a vertical in- 80 and said indicator opera-ting device. y dicator operatin member lsupported for ver- 6. In a load counterbalancing and inditical movement ytape means from said arccatin mechanism for an automatic scale, in uate members, and means interconnecting combination, a pair of oppositely disposed said beam and said indicator operating 'mempendulums, frictionless means for interconber to guide the lower end of said member 85 necting said pendulums, an indicator operatfor movement in a substantially vertical ing device, and frictionless means for mterpath.

connectingsa-id pendulums and said in dica- 9. The `invention set forth in claim 8 in tor operating devlce, said last mentioned which said last mentioned means comprises interconnecting means comprising a tape dea substantially horizonal link interconnect- 40 pending from said pendulums. ing said indicator operatingmember and an 7. In an automatic scale, in combination offset portion of said beam.,

with a. pair of similar oppositely positioned 10. In an automatic scale, in combination, pendulums having arcuate members, frical chart, an indicator, a beam having a load tionless devices constraining said pendulums pivot, a pair o f oppositely disposed pendu,l 45 to operate in liarmon a vertical rack suplums having interconnected arcuate memporting yoke, and frictionless means interbers, a vertical rack member supported from connecting said yoke and said arcuate memsaid arcuate members, and operative connecbers and supporting said \yoke for vertical tions between said beam and said pendulums,

movement. 4 said indicator, load pivot and rack member 50 8. In an automatic scale in combination being substantially. in the central vertical with a beam, an indicator, a pair of oppoplane of the machine and the arcuate porsitely disposed pendulums, an arm extend-` tions of said pendulums being substantially ing laterally from each pendulum towards tangent to said plane. the center of the machine, an arcuate mem-v In'testimony whereof I hereto ax my 55 ber on the end of each of said arms, lsaid signature. l members being substantially tangent to each y other, means comprising tapes for operating WILLIAM `N. GILBERT, 

